Nice themed group of feywild creatures, here are my initial thoughts:
1:Red Capling
I would make Puncturing Thrust an at will power, it is doing less damage than the basic attack and ongoing bleeding damage doesn't stack.
2:Redcap Crook
I would make Heart Thrust an at will that required combat advantage.
Personally I would change Hook Throttle to an attack that grabbed its target then the Crook shifts 3 squares dragging the target with it. This to me would seem more lurker like.
Hook Throttle (standard, encounter)
Attack +6 vs. Fortitude; 1d6+3 or 1d10+3 if blood capped; on hit target is
grabbed (escape ends) and Redcap Crook shifts 3 squares dragging the
grabbed target with it
3:Redcap Warrior
I would make Blood-Capped an at will, not encounter.
I would make Bloody Gut a minor not a standard action, as a standard action it is useless as in the heat of combat you just wouldn't use it over making an attack.
I would also consider dropping the blood capped damage rating on teh basic attack from 1d10+4 to 1d8+4. Soldiers should be high AC low damage.
4:Red Cap Thane
This guy isn't really a controller in the classic sense, I would classify him as a skirmisher. You are also only using the leader tag to stipulate that there can be only one Thane in an encounter, as he doesn't have any leader like abilities.
I would normally expect a controller to use the low and medium damage expressions, the Thane has easy access to the high damage expression with its basic melee attack (this would suit a skirmisher more).
Bloody Changeling needs to explain what happens to any other non damage effects that result from teh attack it is dodging.
I would make Bloody Gut a minor not a standard action, as a standard action it is useless as in the heat of combat you just wouldn't use it over making an attack.